Such an electrohydraulic servo brake is known according to the general prior art. However, with such a servo brake, when the ABS system is actuated, the modulation sends a specific quantity of brake fluid into the main brake cylinder. This becomes evident as a backward movement of the brake pedal, together with weak pressure peaks in the main brake cylinder. These pressure fluctuations are in the order of magnitude of ±30 bar. As a result of the mechanical structure thereof, however, the servo brake with electric motor is a rigid transmission system which does not move backward spontaneously under the action of such loads. This results in an increase of the amplitude of the pressure peaks during this maneuver. This increase may exceed 100 bar so that the transmission of the servo brake is subjected to great fatigue at the expense of the reliability thereof.